Apparatus for lining a borehole as a boring bit advances in the ground



y 2, 1963 M. E. G. TECHY ETAL 3,390,730 APPARATUS FOR LINING A BOREHOLEAS A BORING BIT ADVANCES IN THE GROUND Filed Feb. 25, 1966 2Sheets-Sheet 1 FIG 2 July 2, 1968 M. L. E. e.

' APPARATUS FOR LINING A TECHY ETAL 3,390,730

BOREHOLE AS A BORING IN THE GROUND 2 Sheets-Sheet Z BIT ADVANCES Fil edFeb. 25, 1966 United States Patent Ofice 3,390,730 Patented July 2, 19686 Claims. (a. 175-171 ABSTRACT OF THE DISCLOSURE Apparatus for lining aborehole by inserting a lining element into the borehole in the wake ofa boring bit. The bit is an eccentric member which can be inscribed in acircle of diameter d but which bores a hole of diameter d The liningelement has an internal. diameter d greater than the diameter d in whichthe boring bit can be inscribed and an external diameter d, which issmaller than the hole diameter d such that the boring bit can penetrateeasily into the hole already bored and the boring bit can be inserted inand withdrawn from the lining element.

Our invention relates to apparatus for lining a borehole as a boring bitadvances in the ground.

Systems of this kind are necessary in cases where the ground being boredis a type which can cave in after the boring or drilling bit has passed,with consequent considerable difliculties in drilling; also, the liningmust often be left behind in the borehole if the same is to be usedpermanently.

It is an object of this invention, inter alia in connection with deepholes, to solve the problem economically by means of a lining consistingof commercial tubes.

' In accordance with the invention there is provided apparatus forlining a borehole as a boring bit advances in the ground, said apparatuscomprising a striking element having an eccentric boring bit which canbe inscribed in a circle of diameter d and a lining whose internaldiameter d is greater than the diameter al in which the boring bit canbe inscribed and whose external diameter d is smaller than the holediameter d in such a manner the lining can penetrate easily into thehole already bored and enable the boring bit to be inserted andwithdrawn. The apparatus further comprises a vertical slideway on whichtwo assemblies are movable, the first assembly comprising a firstcarriage and, mounted thereon, a motor for rotating a set of rods towhose lower end the striking element bearing the boring bit isconnected, the second assembly comprising a second carriage, to which amotor is secured, and which is provided with a passage through which therods, striking element and boring bit can pass, the second carriagehaving rigidly connected to it a lining element having secured at itslower end guide projections serving to keep the striking elementcorrectly centered relative to the lining element.

The invention will be described with reference to the accompanyingdrawings which show an exemplary non-limitative embodiment.

In the drawings:

FIG. 1 is a diagrammatic view of the apparatus;

FIG. 2 is a view in enlarged scale of a portion of the apparatus inelevation and partly in section;

FIGS. 3-5 are views of details showing the boring operation and themember of use, and

FIGS. 3a, 4a, 5a are sections on the lines III-III, IVIV and V--V inFIGS. 3, 4 and 5 respectively.

The apparatus comprises a bearing frame 1 which can be, for instance, ofthe tracklaying kind and which can move along the ground and which has avertical slideway 2 (FIGS. 1 and 2); two assemblies 3, 4 are verticallymovable on the slideway 2. The assembly 3 comprises a carriage 5 havingmounted thereon a motor 6 for driving an assembly of rods 7 havingsecured at its lower end a striking element formed by a striking hammer8 having a boring bit 9 at its lower end. A reduced-diameter portion 8narrower than the hammer 8 is provided between the hammer 8 and theboring bit 9. The motor 6 and striking element can be pneumatic, inwhich event they are supplied with compressed air by means of acompressor and air lines (not shown). The system formed by the elements5-9 serves to bore holes in the ground; the assembly of rods 7 isrotated by the motor 6 and drives by its rotation the hammer 8 and theboring bit 9. The bit therefore experiences consecutive blows and arotary movement.

The second system 4 comprises a carriage 10 on which a motor 11 ismounted and which also comprises a passage 12 through which the rods 7,element 8 and boring bit 9 can pass. A lining 13 formed ofinterconnected lining elements is rigidly connected to the carriage 10;guide projections 13 which are, as a rule, four in number are secured tothe lower end of the lining 13 in order to maintain the striking element8 in the correct concentric relationship relative to the lining elementsof lining 13. The assemblies 3, 4 are raised and lowered by winches 14,15 connected respectively to the carriage 5 by a chain 16 running overguide rollers 17, and to the carriage 10 by a chain running over guiderollers 19.

This invention is based on the following principle (FIG. 3):

The striker element in the form of hammer 8 having an eccentric boringbit 9 which can be inscribed in a circle of diameter d bores a hole ofdiameter d greater than the diameter d and the lining 13 has an internaldiameter d greater than d and an external diameter d; smaller than d Thelining 13 has the following capabilities:

(a) it can penetrate readily into the hole already bored,

and

(b) it enables the boring bit 9 to be inserted and withdrawn.

The operation is as follows:

The winches 14, 15 place the assemblies 3, 4 near the top of theslideway 2, as shown in FIG. 2. The various items, namely the liningelement 13, rods 7, hammer 8 and boring bit 9 are brought to theposition shown in FIG. 2. The boring bit 9 is rotated by the rods 7(which are driven by the motor 6) and struck by the hammer 8 and therebydrills or bores a hole of diameter d (FIG. 3) in the ground. The liningelement 13 of diameter d., is rotated by the motor 11 for readypenetration into the ground, penetration being made difficult byfriction between the lining element 13 and the ground. The liningelement 13 therefore penetrates readily into the ground in the wake ofthe boring bit 9.

Once the rods 7 and lining element 13 have completely penetrated intothe ground, they are unscrewed from their drive devices and thecarriages 5 and 10 with the motor 6, 11 are raised by the winches 14,15. Fresh lining elements 13 and rods 7 are screwed to the drives and tothe rods and lining elements already in the ground, and drilling canthen continue.

When drilling is completed and it is required to leave the liningelements in the ground, the drilling elements are withdrawn as follows:

The lining-driving assembly 4 is now at the bottom of the slideway 2.The winch 15 of the assembly 3 raises a the rods 7 slightly until thehammer 8 is raised above the centering projections 13 (FIG. 4) of thedriving element 13 and the projections 13 are opposite the part 8 Themechanism for rotating the rods 7 is then operated to shift the positionof the boring bit 9 as shown in FIG. a so that the centering projections13 take up a position in alignment with the recesses of the boring bit 9so that the bit can enter the lining element 13 when it is raised bymeans of the winch 15 and the cables and pulleys 16, 17 (FIG. 5).Further withdrawal of the elements 79 is then effected by means of thewinch 15 and cable 16.

To remvoe the lining elements 13, the rod-driving assembly 3 is firstraised to the top of the slideway, whereafter the lining elements can beraised by means of the winch 14 and cable 18.

What we claim is:

1. Boring apparatus comprising a vertical slideway, first and secondassemblies supported on the slideway for vertical movement, the firstassembly comprising a carriage,

a rod assembly supported from said carriage, drive means 1 on saidcarriage coupled to said rod assembly for driving the same in rotation,and a striking element constituted as a hammer and an eccentric boringbit, said striking element being coupled to said rod assembly forundergoing rotation therewith, said boring bit being dimensioned suchthat it can be inscribed in a circle of diameter d whereas it generatesa circle of diameter d to bore a hole of such diameter, said secondassembly comprising a second carriage having a passageway through whichthe rod assembly, striking element and boring bit can pass, a liningelement supported by said second carriage and second drive means on thesecond carriage for driving said lining element in rotation, said liningelement encircling the rod assembly and hammer, the boring bit extendingfrom the lining element during a boring operation, said lining elementhaving an internal diameter d which is greater than the diameter d ofthe circle in which the boring bit can be inscribed, and an externaldiameter which is smaller than the diameter d of the hole bored by suchbit under the conjoint action of the rotation of the rod assembly andthe striking movement of the striking element whereby the lining elementcan readily pass through the bored hole and the bit can be inserted andwithdrawn in the lining element, said lining element having a lower endand including guide projections thereat which cooperate with thestriking element to maintain the same in centered relation within thelining element.

2. Apparatus as claimed in claim 1 comprising cables and winches coupledto the first and second assemblies to raise and lower the same along theslideway.

, 3. Apparatus as claimed in claim 1 comprising a hearing frameworkmovable along the ground, said slideway being rigidly connected to saidbearing framework for movement therewith.

4. Apparatus as claimed in claim 9 wherein said rod assembly and liningelement are detachably connected to the first and second assembliesrespectively whereby they may be decoupled and allowed to remain in theground after a boring operation, whereupon the first and secondassemblies can be raised and additional lining elements and rods coupledthereto and to the rod assesmbly and lining element in the groundwhereafter boring can continue.

5. Apparatus as claimed in claim 4 comprising means coupled to the firstand second assemblies to raise and lower the same along the slideway,said lining elements being removable from the bored hole by successivelyraising and lowering the second assembly and decoupling and removing thelining elements one by one.

6. Apparatus as claimed in claim 1 wherein said guide projections faceinwardly and define an opening through which the bit is incapable ofpassing when the striking element is centered in the lining element,said striking element including a portion of reduced diameter betweenthe bit and the hammer enabling the striking element to be raised to aposition in which the portion of reduced diameter is disposed in theopening defined by the guide projections and the hammer is above theguide projections and free thereof whereby the striking element can beshifted laterally in the lining element and the bit withdrawn past theguide projections,

References Cited UNITED STATES PATENTS 1,869,892 8/1932 Grove -171 X2,784,942 3/1957 Peck 175-171 2,979,143 4/1961 Kandle 175-171 X3,190,378 6/1965 Davey 175-171 X NILE C. BYERS, JR., Primary Examiner.

